# AudioConverterFillComplexBufferRealtimeSafe(_:_:_:_:_:_:) ``` func AudioConverterFillComplexBufferRealtimeSafe(_ inAudioConverter: AudioConverterRef, _ inInputDataProc: AudioConverterComplexInputDataProcRealtimeSafe, _ inInputDataProcUserData: UnsafeMutableRawPointer?, _ ioOutputDataPacketSize: UnsafeMutablePointer, _ outOutputData: UnsafeMutablePointer, _ outPacketDescription: UnsafeMutablePointer?) -> OSStatus ``` ## Discussion \abstract Identical to AudioConverterFillComplexBuffer, with the addition of a realtime-safety guarantee. Conversions involving only PCM formats – interleaving, deinterleaving, channel count changes, sample rate conversions – are realtime-safe. Such conversions may use this API in order to obtain compiler checks involving the `CA_REALTIME_API` attributes. At runtime, this function returns `kAudioConverterErr_OperationNotSupported` if the conversion requires non-realtime-safe functionality. --- Copyright © 2026 Apple Inc. All rights reserved. | [Terms of Use](https://www.apple.com/legal/internet-services/terms/site.html) | [Privacy Policy](https://www.apple.com/privacy/privacy-policy)